With the rise in use of small electronic devices such as mobile phones in recent years, there has been a significant increase in the need for designing and producing high quality speakerphones that are small in size. A key design challenge for such small speakerphones is to minimize coupling between the one or more microphones and the one or more speakers. The coupling is composed of acoustic, mechanical, and electrical coupling.
In general, reducing electrical coupling in a speakerphone is less challenging than minimizing acoustic and mechanical coupling. Various methods have been used in the industry to reduce acoustic and mechanical coupling, but most have several disadvantages. For example, some high-quality speakerphones minimize mechanical coupling by using rubber mounts for the speaker and/or microphones. The rubber mounts, however, tend to occupy a lot of space and to be fragile, thus creating a significant design challenge for speakerphones that need to fit within a small space and be robust.
An alternative method of reducing acoustical and mechanical coupling involves creating distance between the one or more microphones and the speaker. This also raises the issue of size in speakerphones which are often designed as accessories for mobile devices or personal computers.